How to describe this issue to the dealer?

Mine does the same thing, it was better after the TSB, but now it's back, I think it's the stall speed on the TC.

 

When I saw this story a month or so back -- I immediately wondered if she was having the same issues with surging as I have. I could understand totally if anyone got in my truck and was not ready for a "strong" up surge in the idle speed would say "what is the deal with this thing" especially if one is the least bit distracted by kiddos or any thing else. In our area we had only a tiny bit of snow and ice last year so I did not experience this issue on slick, snowy, or icy pavement. I am sure this would quickly become a problem on slick pavement --sure you will say --clean your drive -- buuut this is why I have 2 4WD or AWD vehicles.
Like I said before --our 15 Subaru Outback sets the idle higher when it is warming up --then when it comes up to temp it slows itself back down. It is not this unpredictable up and down stuff.
One probably would not even notice this if you were to get in the truck and just pull out into the street and drive on your merry way, but in our case we must back out of our 85 ft driveway to get to the street. Only way around this would be to back the car in. Being we have lived in this same home for 45 years --this has never been a problem till now, and you can guess how many cars and trucks we have used in that amount of time

 

Is "normal" right??

 

I don't think so

 

Could it possibly be your AC compressor engaging/disengaging? It is also on when using defrost.

 

My first thought was A/C as well. Mine will idle hunt when A/C is running stationary.

 

Sounds...Abby....normal